1. Field of the Invention
This invention relates to a camera equipped with a camera shake compensation function that detects camera oscillations and is used to suppress the degradation in picture quality arising from the oscillations.
2. Discussion of Related Art
Currently, conventional camera shake compensating cameras are internally equipped with a camera shake detection device to detect the amount of camera oscillations or "shake". The degradation in picture quality caused by the camera shake is suppressed through the movement of a compensating lens according to the detected amount of shake, as disclosed for example in Japanese Patent Publication No. 50-80845. The camera shake detection devices used with this type of camera shake compensating camera typically include an angular velocity sensor and a component that stores the image of the object being photographed at fixed time intervals, with a CCD used to detect the periodic shake of each resultant image.
When using the angular velocity sensor with the camera shake detection device, the angular velocity induced by the shake of the camera is detected, i.e. changes in the voltage value are detected, and the amount of camera shake based upon angular velocity is determined. When using the component that detects the periodic shake of the stored resultant image on the camera shake detection device, the voltage value is changed, and the amount of camera shake based on the condition of the periodic shake is detected.
In either case, the camera's CPU computes the amount necessary to move the compensating lens, based on the amount of shake detected by the camera shake detection device, and, according to the computed amount, activates the driving motor that moves the compensating lens. After the rotating movement of the motor has been transformed to linear motion through gears, the compensating lens is moved in a direction parallel to the plane of the photographic lens. Thus, the camera shake compensation is accomplished.
Because this type of camera shake compensating camera requires a fixed period of time until the camera shake is detected by the camera shake detection device, a time delay occurs between the actual camera shake and the time that the amount of the shake is output from the camera shake detection device. Particularly, when the component that detects the periodic shake of the stored resultant image is used, the time delay is great because the results of the stored image must be compared at different time intervals. Time is also required for the CPU to compute the amount necessary to move the compensating lens based on the amount of camera shake detected by the camera shake detection device. Furthermore, delays also occur by the time the motor is actually activated based on the computed amount of movement and the driving force reaching the compensating lens through the gears.
However, since conventional camera shake compensating cameras move the compensating lens based on the amount of camera shake detected by the camera shake detection device, and do not account for these time delays, they are unable to correctly compensate for the camera shake that has actually occurred.